One day after Ken Griffey Jr. left the game because of stiffness in the back of his right knee, he reported feeling better Thursday. But in a precautionary decision, the Reds did not start their center fielder against the Cubs. Griffey, who also did not take batting practice Thursday morning, was available to pinch-hit. "He had a little work here early with heat and massage," Reds head trainer Mark Mann said. "It's a lot looser than when he left yesterday." Utility man Ryan Freel started in center field for Cincinnati. The 36-year-old Griffey said he hyperextended his knee chasing fly balls during batting practice Wednesday. He took himself out of the game in the fourth inning after striking out with an awkward swing against Greg Maddux. "With his medical history, we're obviously going to err on the side of caution," Mann said.